Programmable integrated circuits (ICs) are often used to implement digital logic operations according to user configurable input. Example programmable ICs include complex programmable logic devices (CPLDs) and field programmable gate arrays (FPGAs). CPLDs often include several function blocks that are based on a programmable logic array (PLA) architecture with sum-of-products logic. A configurable interconnect matrix transmits signals between the function blocks. Many programmable ICs include hard-wired processors for performing certain functions.
Electrical components within programmable ICs are generally kept within specified operating conditions. For example, electrical components are maintained above a certain minimum voltage and below a certain maximum voltage. Often, monitors are provided on-board the IC to obtain measurements of operating conditions such as voltage for the electrical components within the ICs. These monitors can fail or perform poorly if the monitors are operating outside of specified parameters, such as voltage or temperature. Moreover, because monitors are typically powered by or physically close to the electrical components that they are monitoring, monitors may fail due to operating outside of specified parameters at the same time that the elements being monitored fail. Thus, in many situations, monitors may ineffectively monitor their assigned components.